Endovascular surgery is rapidly advancing and is widely used for the management of various cerebrovascular diseases. Usually, chronic subdural hematomas are treated surgically; however, endovascular surgery is recently being attempted as a new treatment option based on the pathophysiology of this condition.Current Concepts: Chronic subdural hematomas have an outer membrane derived from the dura mater. Sinusoidal capillaries in the outer membrane are a source of bleeding, which leads to hematoma growth and postoperative recurrence. Theoretically, embolization of the middle meningeal artery using endovascular procedures can prevent bleeding from the outer membrane and promote spontaneous resolution of a hematoma. Clinical studies, including recent prospective trials, have demonstrated the superior efficacy and safety of middle meningeal artery embolization over conventional treatment.Discussion and Conclusion: More clinical trials on endovascular surgery for chronic subdural hematomas are forthcoming. We expect that the results of future studies will strengthen the findings of recent prospective trials and contribute to a major shift in the management of chronic subdural hematomas.

Objective: : Surgical site infection is the most detrimental complication following cranioplasty. In other surgical fields, intrawound vancomycin powder application has been introduced to prevent surgical site infection and is widely used based on results in multiple studies. This study evaluated the effect of intrawound vancomycin powder in cranioplasty compared with the conventional method without topical antibiotics. Methods: : This retrospective study included 580 patients with skull defects who underwent cranioplasty between August 1, 1998 and December 31, 2021. The conventional method was used in 475 (81.9%; conventional group) and vancomycin powder (1 g) was applied on the dura mater and bone flap in 105 patients (18.1%; vancomycin powder group). Surgical site infection was defined as infection of the incision, organ, or space that occurred after cranioplasty. Surgical site infection within 1-year surveillance period was compared between the conventional and vancomycin powder groups with logistic regression analysis. Penalized likelihood estimation method was used in logistic regression to deal with zero events. All local and systemic adverse events associated with topical vancomycin application were also evaluated. Results: : Surgical site infection occurred in 31 patients (5.3%) and all were observed in the conventional group. The median time between cranioplasty and detection of surgical site infection was 13 days (range, 4–333). Staphylococci were the most common organisms and identified in 25 (80.6%) of 31 cases with surgical site infections. The surgical site infection rate in the vancomycin powder group (0/105, 0.0%) was significantly lower than that in the conventional group (31/475, 6.5%; crude odds ratio [OR], 0.067; 95% confidence interval [CI], 0.006–0.762; adjusted OR, 0.068; 95% CI, 0.006–0.731; p=0.026). No adverse events associated with intrawound vancomycin powder were observed during the follow-up. Conclusion : Intrawound vancomycin powder effectively prevented surgical site infections following cranioplasty without local or systemic adverse events. Our results suggest that intrawound vancomycin powder is an effective and safe strategy for patients undergoing cranioplasty.

Meningiomas are the most common intracranial tumors. However, microcystic and angiomatous meningiomas are very rare subtypes that present unusual imaging findings. Hence, radiological diagnosis of these tumors can be challenging. We herein describe a case of mixed angiomatous and microcystic meningioma in an 81-year-old male. MRI revealed an extra-axial mass with high T2 signal intensity, measuring 1.5 cm in diameter, with multiple tiny intralesional cysts and entrapped peritumoral cyst formation. After tumor resection, a histopathological diagnosis of mixed angiomatous and microcystic meningioma was made.

Objective: : Endovascular treatment of large, wide-necked intracranial aneurysms by coil embolization is often complicated by low rates of complete occlusion and high rates of recurrence. A flow diverter device has been shown to be safe and effective for the treatment of not only large and giant unruptured aneurysms, but small and medium aneurysms. However, in Korea, its use has only recently been approved for aneurysms <10 mm. This study aims to compare the safety and efficacy of flow diversion and coil embolization for the treatment of unruptured aneurysms ≥7 mm. Methods: : The participants will include patients aged between 19 and 75 years to be treated for unruptured cerebral aneurysms ≥7 mm for the first time or for recurrent aneurysms after initial endovascular coil embolization. Participants assigned to a flow diversion cohort will be treated using any of the following devices : Pipeline Flex Embolization Device with Shield Technology (Medtronic, Minneapolis, MN, USA), Surpass Evolve (Stryker Neurovascular, Fremont, CA, USA), and FRED or FRED Jr. (MicroVention, Tustin, CA, USA). Participants assigned to a coil embolization cohort will undergo traditional endovascular coiling. The primary endpoint will be complete occlusion confirmed by cerebral angiography at 12 months after treatment. Secondary safety outcomes will evaluate periprocedural and post-procedural complications for up to 12 months. Results: : The trial will begin enrollment in 2022, and clinical data will be available after enrollment and follow-up. Conclusion : This article describes the aim and design of a multi-center, randomized, open-label trial to compare the safety and efficacy of flow diversion versus traditional endovascular treatment for unruptured cerebral aneurysms ≥7 mm.

Objective: : The purpose of this study was to evaluate the impact of time interval between index event and stenting on the periprocedural risk of stenting for symptomatic carotid stenosis and to determine the optimal timing of stenting. Methods: : This retrospective study included 491 (322 symptomatic [65.6%] and 169 asymptomatic [34.4%]) patients undergoing carotid stenting. The symptomatic patients were categorized into Day 0–3, 4–7, 8–10, 11–14, 15–21, and >21 groups according to the time interval between index event and stenting. Periprocedural (≤30 days) risk for clinical (any neurological deterioration) and radiological (new infarction on postprocedural diffusion-weighted imaging) events of stenting in each time interval versus asymptomatic stenosis was calculated with logistic regression analysis adjusted for confounders, and provided as odds ratio (OR) and 95% confidence interval (CI). Results: : Overall clinical event rate (4.3%) of stenting for symptomatic carotid stenosis was higher than that for asymptomatic stenosis (1.2%; OR, 3.979 [95% CI, 1.093–14.489]; p=0.036). Stenting in Day 0–3 (13.2%; OR, 10.997 [95% CI, 2.333–51.826]; p=0.002) and Day 4–7 (8.3%; OR, 6.775 [95% CI, 1.382–33.227]; p=0.018) was associated with high risk for clinical events. However, the clinical event rates in stenting after 7 days from index event (Day 8–10, 1.8%; Day 11–14, 2.5%; Day 15–21, 0%; Day >21, 2.9%) were not different from that in stenting for asymptomatic stenosis. Overall radiological event rate (55.6%) in symptomatic stenosis was also higher than that in asymptomatic stenosis (35.5%; OR, 2.274 [95% CI, 1.553–3.352]; p<0.001). The high risk for radiological events was maintained in all time intervals (Day 0–3 : 55.3%; OR, 2.224 [95% CI, 1.103–4.627]; p=0.026; Day 4–7 : 58.3%; OR, 2.543 [95% CI, 1.329–4.949]; p=0.005; Day 8–10 : 53.6%; OR, 2.096 [95% CI, 1.138–3.889]; p=0.018; Day 11–14 : 57.5%; OR, 2.458 [95% CI, 1.225–5.021];p=0.012; Day 15–21 : 55.6%; OR, 2.271 [95% CI, 1.099–4.764]; p=0.028; Day >21 : 54.8%; OR, 2.203 [95% CI, 1.342–3.641]; p=0.002). Conclusion : This study showed that as stenting was delayed, the periprocedural risk for clinical events decreased. The clinical event risk was high only in stenting within 7 days and comparable with that for asymptomatic stenosis in stenting after 7 days from index event, although the radiological event risk was not affected by stenting timing. Therefore, our results suggest that delayed stenting after 7 days from symptom onset is a safe strategy for symptomatic stenosis.

As more intracranial aneurysms and other cerebrovascular pathologies are treated with neurointervention procedure, thromboembolic events that frequently lead to serious neurological deficit or fatal outcomes are increasing. In order to prevent the thromboembolic events, antiplatelet therapy is used in most procedures including coil embolization, stenting, and flow diversion. However, because of variable individual pharmacodynamics responses to antiplatelet drugs, especially clopidogrel, it is difficult for clinicians to select the adequate antiplatelet regimen and its optimal dose. This article reviews the neurointervention literature related to antiplatelet therapy and suggests a strategy for tailoring antiplatelet therapy in individual patients undergoing neurointervention based on the results of platelet function testing.
Aspirin ; Blood Platelets ; Embolization, Therapeutic ; Fatal Outcome ; Humans ; Intracranial Aneurysm ; Pathology ; Platelet Aggregation Inhibitors ; Platelet Function Tests ; Stents

OBJECTIVE: Bilateral cavernous sinus dural arteriovenous fistula (CSdAVF) is very rare, even in Asian countries. The research intended to present clinical and radiologic outcomes of treating such fistulas through endovascular embolization. MATERIALS AND METHODS: Data was obtained from 220 consecutive patients, with CSdAVF, who were treated from January 2004 to December 2015. Bilateral CSdAVF was identified in 17 patients (7.7%). The clinical and radiologic outcomes of the fistulas were assessed with an emphasis on the technical aspects of treatment. RESULTS: At the time of treatment, 7 and 10 patients presented with bilateral and unilateral symptoms, respectively. In the former cases, 4 patients had progressed from unilateral to bilateral symptoms. Bilateral fistulas were treated with a single-stage transvenous embolization (TVE) in 15 patients, via bilateral inferior petrosal sinuses (IPS) (n = 9) and unilateral IPS (n = 6). In the other 2 patients with one-sided dominance of shunting, only dominant fistula was treated. Two untreated lesions were found on follow-up to have spontaneously resolved after treatment of the dominant contralateral fistula. Of the 34 CSdAVF lesions, complete occlusion was achieved in 32 lesions after TVE. Seven patients (41.2%) developed worsening of cranial nerve palsy after TVE. During the follow-up period, 4 patients obtained complete recovery, whereas the other 3 remained with deficits. CONCLUSION: With adjustments of endovascular procedures to accommodate distinct anatomical configurations, endovascular treatment for bilateral CSdAVF can achieve excellent angiographic occlusion results. However, aggravation of symptoms after TVE may occur frequently in bilateral CSdAVF. In the patients with one-sided dominance of shunt, treatment of only dominant fistula might be an alternative option.
Arteriovenous Fistula ; Asian Continental Ancestry Group ; Cavernous Sinus* ; Central Nervous System Vascular Malformations* ; Cranial Nerve Diseases ; Endovascular Procedures ; Fistula ; Follow-Up Studies* ; Humans

Despite advancements in treating ruptured cerebral aneurysms, an aneurysmal subarachnoid hemorrhage (aSAH) is still a grave cerebrovascular disease associated with a high rate of morbidity and mortality. Based on the literature published to date, worldwide academic and governmental committees have developed clinical practice guidelines (CPGs) to propose standards for disease management in order to achieve the best treatment outcomes for aSAHs. In 2013, the Korean Society of Cerebrovascular Surgeons issued a Korean version of the CPGs for aSAHs. The group researched all articles and major foreign CPGs published in English until December 2015 using several search engines. Based on these articles, levels of evidence and grades of recommendations were determined by our society as well as by other related Quality Control Committees from neurointervention, neurology and rehabilitation medicine. The Korean version of the CPGs for aSAHs includes risk factors, diagnosis, initial management, medical and surgical management to prevent rebleeding, management of delayed cerebral ischemia and vasospasm, treatment of hydrocephalus, treatment of medical complications and early rehabilitation. The CPGs are not the absolute standard but are the present reference as the evidence is still incomplete, each environment of clinical practice is different, and there is a high probability of variation in the current recommendations. The CPGs will be useful in the fields of clinical practice and research.
Aneurysm ; Brain Ischemia ; Cerebrovascular Disorders ; Diagnosis ; Disease Management ; Hydrocephalus ; Intracranial Aneurysm ; Mortality ; Neurology ; Quality Control ; Rehabilitation ; Risk Factors ; Search Engine ; Subarachnoid Hemorrhage ; Surgeons

BACKGROUND AND PURPOSE: Measuring the extent of the collateral blood vessels using computed tomography (CT) angiography source images may promote tissue survival and functional gain in acute ischemic stroke patients who are candidates for endovascular recanalization treatment. METHODS: Of 5,558 acute stroke patients registered in a prospective clinical stroke registry, 104 met the selection criteria of endovascular recanalization treatment for internal cerebral artery or middle cerebral artery main-stem (M1) occlusions and presented for treatment ≤4 hours after the event. Using CT angiography source images, two independent and blinded reviewers measured the extent of collateral circulations at four regions, with good interrater reliability. The functional recovery at 3 months after stroke was used as an outcome variable. RESULTS: Cases with a sufficient collateral circulation at the Sylvian fissure showed significantly increased likelihood of having a modified Rankin Scale score of ≤2 at 3 months after stroke (adjusted odds ratio=3.03, 95% confidence interval=1.19–7.73, p=0.02), but the association became nonsignificant after adding the infarct volume to the model (p=0.65). The association between leptomeningeal convexity collaterals and functional recovery was no longer significant after adjusting for the infarct volume (p=0.28). The natural indirect effect of infarct volume on functional recovery was significant for both the Sylvian fissure (p=0.03) and leptomeningeal convexity (p=0.02) collaterals. CONCLUSIONS: The extent of collateral circulation at the Sylvian fissure was significantly associated with functional recovery, which may be mediated via the volume of the final infarction.
Angiography* ; Blood Vessels ; Cerebral Arteries ; Collateral Circulation ; Humans ; Infarction ; Middle Cerebral Artery ; Mortality ; Patient Selection ; Prospective Studies ; Stroke* ; Tissue Survival

OBJECTIVE: Outcomes of stent-assisted coil embolization (SACE) have not been well established in the setting of vertebrobasilar dissecting aneurysms (VBDAs) due to the low percentage of cases that need treatment and the array of available therapeutic options. Herein, we presented clinical and radiographic results of SACE in patients with VBDAs. MATERIALS AND METHODS: A total of 47 patients (M:F, 30:17; mean age ± SD, 53.7 ± 12.6 years), with a VBDA who underwent SACE between 2008 and 2014 at two institutions were evaluated retrospectively. Medical records and radiologic data were analyzed to assess the outcome of SACE procedures. Cox proportional hazards regression analysis was conducted to determine the factors that were associated with aneurysmal recanalization after SACE. RESULTS: Stent-assisted coil embolization technically succeeded in all patients. Three cerebellar infarctions occurred on postembolization day 1, week 2, and month 2, but no other procedure-related complications developed. Immediately following SACE, 25 aneurysms (53.2%) showed no contrast filling into the aneurysmal sac. During a mean follow-up of 20.2 months, 37 lesions (78.7%) appeared completely occluded, whereas 10 lesions showed recanalization, 5 of which required additional embolization. Overall recanalization rate was 12.64% per lesion-year, and mean postoperative time to recanalization was 18 months (range, 3-36 months). In multivariable analysis, major branch involvement (hazard ratio [HR]: 7.28; p = 0.013) and the presence of residual sac filling (HR: 8.49, p = 0.044) were identified as statistically significant independent predictors of recanalization. No bleeding was encountered in follow-up monitoring. CONCLUSION: Stent-assisted coil embolization appears feasible and safe for treatment of VBDAs. Long-term results were acceptable in a majority of patients studied, despite a relatively high rate of incomplete occlusion immediately after SACE. Major branch involvement and coiled aneurysms with residual sac filling may predispose to recanalization.
Aneurysm ; Aneurysm, Dissecting* ; Embolization, Therapeutic* ; Follow-Up Studies ; Hemorrhage ; Humans ; Infarction ; Medical Records ; Retrospective Studies ; Stents